| 作者单位 |
1. College of Horticultural Science and Technology, Hebei Normal University of Science and Technology, Qinhuangdao 066004, China; 2. Engineering Research Center of Chestnut Industrial Technology, Ministry of Education, Hebei Qinhuangdao 066004, China; 3. Key Laboratory of Germplasm Mining and Innovative Utilization ofCharacteristic Horticulture, Hebei Province, Qinhuangdao 066004, China; 4. Hebei chestnut Industry Collaborative Innovation Center, Qinhuangdao 066004, China |
| 摘要 |
[Objectives] This study was conducted to investigate the differences of photosynthetic physiological characteristics of different varieties (strains), which will provide a theoretical basis for high photosynthesis efficiency breeding and application in Chinese chestnut. [Methods] Six Chinese chestnut varieties of Castanea mollissima 'Yanbao', C. mollissima 'YanQiu', C. a mollissima 'Yanchang', C. mollissima 'Yanjia', C. mollissima 'qianxi 37', and C. mollissima 'hybrid 22' were used as the materials. Using the portable photosynthesis system Li-6400, we measured the photosynthetic characteristics and diurnal variation of leaf samples of 6 different chestnut varieties or strains. We fitted the light response curves and photosynthetic parameters using the leaf floating model. Additionally, we determined the chlorophyll content in the leaves using a UV-visible spectrophotometer. [Results] Among the six chestnut varieties or strains, 'Yanqiu' exhibited a significantly higher photosynthetic light saturation point (PLSP) compared to the other 5 varieties, and 'hybrid 22' ranked second, indicating that these two varieties had the strongest adaptation to high light intensity. The photosynthetic light compensation point (PLCP) of 'Yanchang' was significantly higher than other five varieties, and "Qianxi 37" ranked second, indicating that these two varieties had the strongest adaptation to low light intensity. Additionally, they exhibited higher chlorophyll content and maintained good photosynthetic characteristics even in shaded environments with weak light stress. Varieties 'Yanbao' and 'Yanjia' showed higher PLSP and lower PLCP, indicating that these two varieties have a wider range of adaptation to light intensity. They were capable of efficiently utilizing light across a broader spectrum of intensities. 'Yanqiu' had the highest maximum net photosynthetic rate (Pn, max) and the lowest dark respiration rate (Rd), along with the highest chlorophyll content. It indicated that 'Yanqiu' has strong photosynthetic capacity and organic matter accumulation ability. It also had the highest PLSP, enabling it to fully utilize the high light environment of the Yanshan Mountains and possessed high light efficiency characteristics. The Pn, max of 'Yanqiu' was significantly higher than other varieties. 'Hybrid 22' and 'Yanbao' also exhibited significantly higher Pn, max compared with 'Yanjia'and 'Qianxi 37'. 'Yanchang' had the lowest Pn, max. The order of Pn, max among the six chestnut varieties or strains was as follows: 'Yanqiu'>'Hybrid 22'>'Yanbao'>'Yanjia'>'Qianxi 37'>'Yanchang'. |
